This invention relates to the protection from the effects of air-outflow from an air-conditioning airflow structure. More particularly, this invention relates to the field of protecting ceiling tiles, and other ceiling components that surround an air diffuser, from damage due to moisture, dirt, dust, grease and other particulates that may emanate from the diffuser and its connecting components.
The art of directing air flow into defined enclosed spaces, such as rooms in buildings, aircraft compartments, ship compartments, and the like, employs a variety of designs and technologies used in a wide range of conditions. A common system employs rigid or flexible ductwork directing air from a source of pressurized air (such as a heating or air conditioning unit) through one or more air inflow structures into the defined spaces. A connecting means typically connects the outflow end of a flexible duct to the diffuser, which typically comprises a boot structure integral with a grill device that directs air into a room. Depending on the insulation properties of the boot, and the ambient humidity, condensate may form on its exterior surface and travel downward to the edges of the diffuser structure.
The final air delivery structure directing air into the defined space, from a ceiling, is referred to, among other terms, as a diffuser, register, or supply grill. For the purposes of this specification, this will be referred to as a diffuser to represent the variety of possible air delivery structures that direct air into a room from a ceiling surface. For purposes of this invention, this term represents, and is interchangeable with, the term xe2x80x9cair delivery structurexe2x80x9d. These terms, diffuser and air delivery structure, include the combination of the boot and the actual grillwork connected to the grill that directs the air into the room.
It has been observed in some applications, such as restaurants, that one or more ceiling tiles immediately adjacent to a diffuser become stained due to having received moisture from water condensation from the boot, from the outer edges of the diffuser, or from both. This condensation collects and can travel to an adjacent tile, causing a stain. The stain is aesthetically displeasing, and may also harbor bacteria or molds that can contribute to air quality deterioration and xe2x80x98sick building syndromexe2x80x99. Additionally, the condensation has been observed to cause rust and other deterioration, such as loss of surface paint, on the suspended ceiling support grids immediately adjacent to the diffuser. In extreme conditions, the saturation of adjacent tiles may result in the tiles falling, causing injury to persons or equipment. Also, another extreme condition may be when a puddle forms from excessive condensation falling below the diffuser, possibly resulting in slip-and-fall type injuries to persons traveling below.
Another problem that has been observed is the noticeable depositing of dirt stains on ceiling tiles and other ceiling structures adjacent to a diffuser. This appears to be due to a combination of factors, including but not limited to at least some of the following: infrequent changing of air system filters; heavy load of particulates in the air leaving the diffuser; and the diffuser directing air near or onto the adjacent ceiling structures.
For these reasons, a simple, effective means of preventing this deterioration and risk of injury is needed. The present invention solves the problem of excessive condensate moisture collecting around or on diffusers, and does this in a simple and relatively inexpensive manner. The present invention, in preferred embodiments, also reduces or eliminates the deposition of staining material onto the adjacent ceiling structures from the diffuser outflow air.
Other devices are known that attempt to solve diffuser-related condensation problems. For instance, U.S. Pat. No. 5,657,636 teaches applying heat transfer tape around the perimeter of a concentric diffuser (e.g., a circular diffuser supplying cool air around the perimeter and drawing return air into the center portion). A humidistat positioned in the return side of the air conditioning unit, upon sensing an elevated humidity level, trips a relay to send current to the tape, heating the tape. The tape is said to heat the supply grill, thereby preventing moisture condensation accumulation.
In contrast, U.S. Pat. No. 5,211,605 teaches an air conditioner diffuser assembly constructed of molded inorganic fiber material cured with a binder. This material, having a low thermal conductivity, thereby prevents (or minimizes) condensate accumulation on this diffuser. One drawback to this invention is the need to replace existing diffusers with this specially fabricated diffuser. Where the existing diffusers are in good condition, this would appear wasteful of assets.
Another reference directed to solving the condensation problem using a different solution is U.S. Pat. No. 5,778,147. This patent teaches use of a heater to heat the grilles of an air discharge port of a room air conditioner.
The present invention solves the problems of moisture deterioration and staining of adjacent ceiling tiles, support grids, and other adjacent ceiling components. In addition, by preventing or reducing the exposure of ceiling tiles to moisture, the present invention reduces the likelihood of mold growth on such tiles. This is advantageous in light of recent concerns about mold and other microorganism growth in buildings, which has been shown in some cases to be causative or a contributing factor in xe2x80x98sick building syndrome.xe2x80x99
The present invention provides an article of manufacture herein termed a barrier device, barrier means or protective device, and related methods and kits that protect ceiling tiles, ceiling support structures, and other ceiling components adjacent to an air delivery structure, herein also referred to as a diffuser, from exposure to moisture due to condensation at the edges of the air delivery structure. Embodiments of the invention also protect these ceiling components from deposition of dirt, dust, grease, moisture droplets, and other particulates being carried in the delivered air.
In one embodiment of this invention, a water-impermeable multi-faceted device is constructed to closely fit between the ceiling support structure and a diffuser whose external edges would otherwise contact the support structure. The device is comprised of at least two facets. An inner partition separates the side edges of the diffuser from the components of the ceiling support structure and/or the abutting ceiling tiles that lie immediately to the sides of the diffuser. A platform facet, integrally attached to the inner partition and substantially parallel to the ceiling plane, separates the lower-side edges of the diffuser from the underhanging ceiling support structure.
The inner partition and platform facets form a continuous, water-impermeable border around the diffuser, matching the outer shape of the diffuser (e.g., square, rectangular, circular, etc.). Condensation that collects on the inside faces of this device either remains there until it evaporates, or travels downward and away from the ceiling components. This protects the ceiling components from the degradative effects of condensation coming from the diffuser.
In another, preferred embodiment, the device additionally comprises a third facet, integral to and oriented below the interior end of the platform, projecting generally downward, away from the diffuser and toward the space receiving the air. This third facet is termed a deflecting partition; it serves to deflect air from passing close to or against the adjacent ceiling components. It has been observed in some air conditioning applications, such as in restaurants, that ceiling tiles adjacent to diffusers become noticeably dirty. This dirt comes from the diffuser, and often is related to high particulate levels in the air. The deflecting partition shields the adjacent ceiling components from nearby and direct airflow, and thereby prevents or minimizes the deposition of dirt, dust, grease, moisture droplets, and other particulates that are in the diffuser""s air discharge.
The present invention, in other embodiments, incorporates the above-described features in newly designed diffusers rather than a separate barrier device. Additional objects, advantages, and novel features of the invention will be set forth in part in the description that follows, and in part will become apparent to those skilled in the art upon examination of the following, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.